Threaded rod is provided in substantial lengths and is widely used to construct or hang utilities or other items. It is also used as tie-rods and has many purposes. The rod can be of substantial length such as several meters or more. To thread a conventional nut on a rod of such length requires many turns and is a dull and time consuming job. In many hanger or fastening situations, the ends of the rod may be blocked with something already installed or fixed, and to put another nut on the rod could require substantial disassembly. It would, of course, be desirable to be able to position the nut on the rod laterally at the desired position and then simply tighten it with a few turns.
Many and varied solutions to these problems have been proposed. A typical solution is that found in U.S. Pat. No. 4,826,376 to Slip-on Lock Nut Company of Lake Orion, Mich. U.S.A. The two C-shaped nut members are joined together for limited axial movement and relative rotation. The two parts are complex and the nut, while effective, is costly. Others are overly complex or simply don't function as a conventional nut which can be tightened after being slipped on. Others occupy too much vertical or axial space along the rod. Others simple don't have the holding power to clamp a load or may slip under load, particularly an offset load.
Examples of the wide variety of devices which have attempted to solve the problem are seen in the following: U.S. Pat. Nos. 3,844,518, 4,473,205, 4,634,327 and 5,098,241 and European Published Application 066644A1.